Electrical connector



Jan. 4, 1966 J. A. NAVA ELECTRICAL CONNECTOR Filed Sept. 12, 1965 INVENTOR. cfoswgafi A J 62 BY I x M 2461/ w W" ATTOR E YS United States Patent 3,227,990 ELECTRICAL CONNECTOR .loseph A. Nara, Viila Park, Ill., assignor to The Pylelglational Company, Chicago, 111., a corporation of New ersey Filed Sept. 12, 1963, Ser. N 308,489 2 Claims. Cl. 339-94 The present invention generally relates to electrical connectors and more particularly relates to an electrical connector wherein a rubber insulator is sandwiched between two rigid insulator parts for receiving and retaining insertable contact members and wherein the relationship of the diameters of the contacts and the rigid insulation parts together with the dimensions of the rubber seal are such that the contacts are insertable without detrimental effect on the rubber.

In accordance with this invention, a sealing concept for a multiple pin connector is contemplated which utilizes a rubber insulation sandwiched between two rigid insulation parts, such that in each contact cavity a portion of the rubber protrudes into the cavity. When a contact is inserted in that cavity, the front end of the contact displaces the rubber and its insertion is continued to the point at which the contact occupies its normal operating position, whereupon the rubber snaps into a groove in the contact body. The rubber in the groove operates in a flapper fashion, such that pressure on one side or the other will cause displacement of the rubber to the contact shoulder on the opposite side of the pressure, thereby increasing the sealing efficiency. Sealing at low pressure differentials is accomplished by initial interference between the shoulders and the corresponding diameters and the rubber.

It is an object of the present invention, therefore, to provide an imroved multi-pin electrical connector having combined contact-retention and contact-sealing means.

Yet another object of the present invention is to provide a connector assembly utilizing a three-piece insert sandwich arangement for improved contact retention and contact sealing.

It is still another object of the present invention to provide an electrical connector with a three-piece sandwich assembly for contact sealing with said sealing assembly operating in a flapper fashion.

It is another object of the present invention to provide electrical connector with a three-piece sandwich assembly for contact sealing wherein the cross-sectional area of the clearance between the contact surface and the contact bore in the electrical connector is approximately 20-50% of the cross-sectional area of the contact bore.

It is further another object of the present invention to provide an electrical contact with a three-piece sandwich assembly to employ a unique combination contact sealing wherein the center member is a flexible sealing member that snaps into a groove in the contact body in such a manner that pressure on one side or the other of said member will cause displacement thereof to engage the contact shoulder on the opposite side of the pressure and thereby increase the sealing efficiency.

Other features, advantages and additional objects of the present invention will be apparent to those skilled in the electrical connector art particularly after consideration of the following detailed description and drawing illustrating a preferred embodiment of the present invention wherein like reference numerals refer to like parts.

On the drawing:

FIGURE 1 illustrates an elevational view of the electrical connector of the present invention; and

FIGURE 2 illustrates a partial cross-sectional view of the electrical connector of the present invention illustrated in FIGURE 1 with parts in elevation.

As shown on the drawings:

Although the principles of the present invention are of general applicability, a particularly useful application is made to a multi-pin electrical contact member wherein assembly procedures require that the contact members be inserted into an insulation carrier.

To insert contacts without damage and to understand the conditions attendant upon such operation, it is necessary to differentiate between shearing and drawing conditions. If the contact is visualized as a punch and the hole in a rigid insulator as a hole in the die and the rubber as a piece of stock interposed between the punch and the die, it will be apparent that if the clearances are small, the rubber will be sheared between the punch and the die. On the other hand, if the clearances between the punch and the die are very large, the punch will draw the rubber into the hole of the die, thereby effectively drawing or ironing the rubber.

Neither condition is desirable in a connector assembly as illustrated generally in the drawings.

In accordance with the principles of the present invention, an area has been determined between the extreme conditions which will yield suitable displacement of the rubber during contact entry, but yet will provide the ability to recover and provide an adequate seal between the parts.

It is contemplated by the present invention that when a contact is inserted into the cavity of a connector, the front end will displace the rubber insulation sandwiched between two rigid insulator parts and when insertion is continued, the contact will occupy its normal operating position when the rubber snaps into a groove in the contact body. The rubber in the groove operates in a flapper fashion, such that pressure on one side or the other will cause displacement of the rubber to the contact shoulder on the opposite side of the pressure, thereby increasing the sealing ef fiiency.

By utilizing a clearance between the contact bore and the contact outer surface which is 20% to of the thickness of the rubber seal, it is possible to prevent undesirable shearing of the rubber, drawing of the rubber or ironing of the rubber. Moreover, little resistance to the insertion of the electrical contact is encountered even though completely automatic sealing of the contact is afforded.

Referring to FIGURES 1 and 2, there is illustrated an electrical connector 11 having a male component indicated at M and a female component indicated at F. The two components M and F constitute separable members of a multi-pin or a multi-contact connector assembly of the present invention.

The male component M has a cylindrical housing 12 internally structured to receive a mounting means 13 for retaining a plurality of male contact members 14 and a rigid thin sleeve or tube 16 and a split ring member 88 around the mounting means 13. The mounting means 13 is retained by the split ring member 88 and positioned by the sleeve 16. The sleeve 16 is retained in position by a nut member 17 which is internally threaded for engagement with an externally threaded portion of the housing 12. The cylindrical male housing 12 has a radially outwardly extending rib 18 for bottoming a sealing ring (not shown) on one side 18a and shouldering on its opposite side 18]) a flange of an internally threaded nut (not shown).

Internally, the male housing 12 has a chamber 19 in which male contact portions 21 of the male currentcontinuing members 14 are adapted to be positioned. At the end of the cylindrical chamber 19 there is provided a radially inwardly extending flange 22 bottoming on the back shoulder thereof a pre-stressed resilient biasing means 23 yieldably deforming in an axial direction.

A grooved recess 24 is formed in the housing 12 adjacent the back shoulder of the flange 22 to confine the biasing means 23.

Extending away from the grooved recess 24 is a smooth cylindrical bore wall 26 with internal keys which is adapted to closely receive the peripheral surface of a resilient rubber sealing member 27 of the male mounting means. The inner diameter of the bore wall is preferably of somewhat smaller diameter than the outer diameter of the sealing member 27 to yieldably deform the periphery of the sealing member 27 for improving the seal between the housing 12 and the mounting means 13.

The female component F has a housing 28 having a cylindrical chamber 29 sized to receive in telescoping relation the end of the housing 12 and providing a radial end wall 31 for sealingly engaging against the sealing member abutting the male flange shoulder 18a. The housing 28 has one end externally threaded at 32 so that the male component M may be locked in join-together relationship with the female component F by threading a nut member onto the female housing 28.

A tool engaging flange 33 is formed on the female housing 28 with the other end thereof threaded as at 34 for cooperation with a nut member 17 similar to the nut member already described and therefore identified by the same reference numeral 17.

In general, the female housing 28 is grooved as at 36 in the same manner as the groove 24 in the male housing 12, to thereby receive a biasing means again indicated at 23 since the function is the same as the biasing means 23 already described. It will be understood that the female component F is assembled in the same manner as the male component M in that the female current-com tinuing contacts 38 are mounted by mounting means 39 similar to male mounting means 13 and has a tubular member 16 around the mounting means 39 which is retained by a split ring 88 and positioned by the nut 17.

Each male contact 14 has a socket portion 44 terminating in a first radially enlarged circumferentially continuous rib 45. Spaced from the rib 45 is a second rib 46 having substantially the same outer diameter as the first rib and forming with the first rib as a male contact groove 47 having a forward shoulder 48 and a back shoulder 49. Extending inwardly from the second rib 46 is the contact body portion 50 which converges into the reduced diameter cylindrical male insertion portion 21.

The male mounting means 13 has two rigid cylindrical insulating members 41 and 43 and the cylindrical resilient rubber seal member 27 sandwiched between insulating members 41 and 43. The back insulating means 41 has formed therethrough a plurality of cylindrical passages 51 that have an inner diameter larger than the diameter of the first male contact rib 45 and has an outer surface 52 that has a stepped configuration so as to be spaced approximately an equal distance from the inner walls of the tube 16 and inner housing walls 26. The back insulation member 41 has inward projections which retain collet 53 mounted in each passage 51 flush with the inner walls thereof. The collets 53 have tines 54 that engage the back shoulder of the rib 45 to retain the male contact in the connector.

The forward insulation member 43 has an outer surface 58 with a second configuration that is spaced from the housing wall 26 and has a shoulder 59 for bottoming the biasing means 23. The for-ward insulation members are counterbored at each end to form a cylindrical passage 61 having a diameter slightly larger than the diameter of the contact body 50; a back counterbored cylindrical contact bore 62 having a diameter equal to the diameter of the back insulation member contact bore 57 and in contact with the forward face of the rubber seal 27 and a forward counterbored passage 63.

The rubber seal means 27 is sandwiched between the back insulation member 41 and the forward insulation member 43 with the mouths of their respective contact bores 57 and 62 in sealing contact with opposite faces of the rubber seal. Both of the insulation members 41 and 43 have chamfers 63 and 64 respectively on their facing end walls to pinch and securely grasp the rubber seal as illustrated in FIGURE 2. The outer diameter of the rubber seal is larger than the diameter of the housing wall 26. Therefore, when the mounting member 13 is inserted in the housing 12, the outer periphery of the seal 27 is compressed, as indicated at 65 to seal the housing 12.

A plurality of holes 66 are formed through the rubber seal and are set to be concentric with respective insulator passages 56 and 61. The seal holes have a diameter smaller than the diameter of the male contact groove 47 and a thickness smaller than the distance between the back and forward shoulder of the contact groove. Also, the amount of protrusion of the rubber seal is such that the rubber seal will be compressed and present pressure surfaces of 67 and 68 in abutting sealing relation against groove shoulders 48 and 49 respectively in a low pressure system illustrated in FIGURE 2 or in flapper sealing arrangement.

Extending from the shoulder 56 is a reduced medial section 47 which extends to a second rib 58 having a rear shoulder 49 and having a diameter substantially equal to the diameter of the rib 44.

The female contact member 38 has a female receiving portion 71 with a male receiving cavity 71a formed therein, a contact grooves portion 72 having a forward shoulder 73 and a back shoulder 74; a rib portion 75 having a diameter equal to the diameter of the female receiving portion 71 and forming the groove 72 therewith; and a reduced diameter socket portion 76.

The female contact mounting means 39 is similar to the male mounting means 13. The mounting means has a rear rigid insulating member 77 having a collet means 53 embedded in each cavity thereof for retaining the female contacts 38 in the connector and being similar to the insulating member 41; a rubber seal 79 similar to the rubber seal 27; and a front insulating member 81 sandwiching the rubber seal 79 between it and the back insulating member.

The front female insulating means has a plurality of counterbored elongated contact bores 82 formed therein concentric with a plurality of holes 83 in the front end thereof for receiving the male contact insertion portions 21. Also, the back insulator 77 has a plurality of counterbores to form contact bore portions 84 wherein the mouth thereof abuts the back face of the rubber seal 79 and the mouth of the bores 82 abut the front face of the rubber seal 79. The dimensional characteristics of the contact bore, the rubber seal, the female mounting means are identical to that described previously in connection with the male portion M of the connector 11. The rubber seal with its plurality of contact passages must be dimensioned the same as rubber seal 27 to provide the improved sealing of the present invention.

Since the connector illustrated herein is designed to seal at low pressure differentials as well as high pressure differentials, the rubber seal 79 is compressed by the female contact grooves 72 and has surfaces 86 and 87 in pressure contact with the grooves shoulders 73 and 74 respectively.

As is noted in FIGURE 2, the thickness of the rubber seals 27 and 79, which are sandwiched between two rigid insulation members; the diameter of the passageways in the insulation members and the rubber seals are predetermined so that when the male and female contacts are inserted into the connector 11 the rubber seals will be compressed at their passageways to define pressure surfaces that engage both of the male contact groove shoulders. In this manner, the rubber seal operates in a flapper fashion such that for example referring to the male contact 14, when pressure is exerted on the back side of the rubber seal the pressure acts on the pressure surface 67 to cause displacement of the rubber towards the opposite shoulder 49 to thereby increase the sealing efiiciency of the rubber seal.

The pressure surfaces are diverging surfaces, i.e., male rubber seal pressure surfaces 67 and 88 and female rubber seal pressure surfaces 86 and 87, that are formed by compressing the rubber seals between two rigid insulators. The pressure surfaces allow the rubber seal to effectively act as a flapper seal. Sealing at low pressure differentials is accomplished by initial interference between these pressure surfaces and both shoulders of the contact groove.

Therefore, I have provided a connector having an improved single multi-contact sealing means which requires little or no attention or care on the part of the user when inserting a contact into the connector and which eliminates the necessity of individual sealing means on each electrical contact.

Although minor modifications might be suggested by those versed in the art, it should be understood that I with to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contributions to the art.

I claim as my invention:

1. In a multi-contact connector,

a disk-shaped mass of resilient dielectric material forming a rubber sealing disk,

said disk having a plurality of separate openings through which the contacts extend,

a pair of rigid insulators substantially coextensive with and adjacent to opposite sides of said rubber sealing disk and each having a plurality of separate bores disposed concentrically with respect to said openings in said rubber sealing disk,

each said insulator having an end Wall facing said rubber sealing disk,

the inner edge of each said bore being counterbored at said end wall, the outer peripheral edge of each said rigid insulator being chamfered to pinch and securely engage the adjoining portions of said rubber sealing disk,

a housing having a cylindrical bore receiving said rubber sealing disk and said rigid insulators,

means in said housing for clamping said rigid insulators against said rubber sealing disk and having passages through which the contacts extend,

a contact member insertable through one of said passages and through a corresponding one of said bores of said rigid insulators and through a corresponding one of said openings of said rubber sealing disk,

said contact member having a reduced portion formed between facing shoulders, said counterbores in said rigid insulators and the outer peripheral portions of said facing shoulders having a clearance space therebetween which is equal to 20% to of the thickness of said rubber sealing disk, thereby to prevent shearing, drawing or ironing of the rubber during insertion of the contact member,

the outer diameter of said rubber sealing disk being greater than the diameter of said cylindrical bore in said housing, thereby to force rubber sealing material into the chamfered portions of said rigid insulators when clamped,

said openings in said rubber sealing disk being smaller in diameter than the diameter of the corresponding reduced portion in said contact member and the thickness of said rubber sealing disk being smaller than the axial spacing dimension between said facing shoulders but of sufiicient thickness to protrude and present a portion of sealing material in a corresponding counterbore forming a barrier in said counterbore between adjacent contact members, said facing shoulders being disposed in said counterbores and each said barrier constituting a circumferentially continuous annulus in said clearance space for sealably engaging said shoulders and said rigid insulators. 2. In a multi-contact connector as defined in claim 1, collet retention means between said means in said housing and said contact member to help retain said contact member in assembled relation.

References Cited by the Examiner UNITED STATES PATENTS JOSEPH D. SEERS, Primary Examiner.

W. D. MILLER, Assistant Examiner. 

1. IN A MULTI-CONTACT CONNECTOR, A DISK-SHAPED MASS OF RESILIENT DIELECTRIC MATERIAL FORM ING A RUBBER SEALING DISK, SAID DISK HAVING A PLURALITY OF SEPARATE OPENINGS THROUGH WHICH CONTACTS EXTEND, A PAIR OF RIGID INSULATORS SUBSTANTIALLY COEXTENSIVE WITH AND ADJACENT TO OPPOSITE SIDES OF SAID RUBBER SEAL ING DISK AND EACH HAVING A PLURALITY OF SEPARATE BORES DISPOSED CONCENTRICALLY WITH RESPECT TO SAID OPENINGS IN SAID RUBBER SEALING DISK, EACH SAID INSULATOR HAVING AN END WALL FACING SAID RUBBER SEALING DISK, THE INNER EDGE OF EACH SAID BORE BEING COUNTERBORED AT SAID END WALL, THE OUTER PERIPHERAL EDGE OF EACH SAID RIGID INSULATOR BEING CHAMFERED TO PINCH AND SECURELY ENGAGE THE ADJOINING PORTIONS OF SAID RUBBER SEALING DISK, A HOUSING HAVING A CYLINDRICAL BORE RECEIVING SAID RUBBER SEALING DISK AND SAID RIGID INSULATOR, MFANS IN SAID HOUSING FOR CLAMPING SAID RIGID INSULATORS AGAINST SAID RUBBER SEALING DISK AND HAVING PASSAGES THROUGH WHICH THE CONTACTS EXTEND, A CONTACT MEMBER INSERTABLE THROUGH ON OF SAID PASSAGES AND THROUGH A CORRESPONDING ONE OF SAID BORES OF SAID RIGID INSULATORS AND THROUGH A CORRESPONDING ONE OF SAID OPENINGS OF SAID RUBBER SEALING DISK, SAID CONTACT MEMBER HAVING A REDUCED PORTION FORMED BETWEEN FACING SHOULDERS, SAID COUNTERBORES IN SAID RIGID INSULATORS AND THE OUTER PERIPHERAL PORTIONS OF SAID FACING SHOULDERS HAVING CLEARANCE SPACE THEREBETWEEN WHICH IS EQUAL TO 20% TO 60% OF THE THICKNESS OF SAID RUBBER SEALING DISK, THEREBY TO PREVENT SHEARING, DRAWING OR IRONING OF THE RUBBER DURING INSERTION OF THE CONTACT MEMBER, THE OUTER DIAMETER OF SAID RUBBER SEALING DISK BEING GREATER THAN THE DIAMETER OF SAID CYLINDRICAL BORE IN SAID HOUSING, THEREBY TO FORCE RUBBER SEALING MATERIAL INTO THE CHAMFERED PORTIONS OF SAID RIGID INSULATORS WHEN CLAMPED, SAID OPENINGS IN SAID RUBBER SEALING DISK BEING SMALLER IN DIAMETER THAN THE DIAMETER OF THE CORRESPONDING REDUCED PORTION IN SAID CONTACT MEMBER AND THE THICKNESS OF SAID RUBBER SEALING DISK BEING SMALLER THAN THE AXIS SPACING DIMENSION BETWEEN SAID FACING SHOULDERS BUT OF SUFFICIENT THICKNESS TO PROTRUDE AND PRESENT A PORTION OF SEALING MATERIAL IN A CORRESPONDING COUNTERBORE FORMING A BARRIER IN SAID COUNTERBORE BETWEEN ADJACENT CONTACT MEMBERS, SAID FACING SHOULDERS BEING DISPOSED IN SAID COUNTERBORES AND EACH SAID BARRIER CONSTITUTING A CIRCUMFERENTIALLY CONTINUOUS ANNULUS IN SAID CLEARANCE SPACE FOR SEALABLY ENGAGING SAID SHOULDERS AND SAID RIGID INSULATORS. 